Investigators looking into the military intelligence unit’s alleged wrongdoings are seeking an extension and more personnel for the probe, local media reported Tuesday.

According to reports citing unnamed Ministry of National Defense sources, the team requested Defense Minister Song Young-moo approve a 30-day extension on Tuesday.

Defense Security Command in Gwacheon, Gyeonggi Province. Yonhap

The team of military and civilian prosecutors is looking into allegations the Defense Security Command drew up detailed plans for implementing martial law during the protests that led to the impeachment of President Park Geun-hye last year. The DSC is also alleged to have surveilled families of the Sewol ferry accident victims.

Under related regulations, the team can request three 30-day extensions if it is unable to reach a conclusion within 40 days of its launch. The initial investigation period is set to expire on Aug. 20.

According to reports, Song is said to have approved the extension, and the investigators are also hoping to bring in additional 10 investigators.

So far in the investigation, it has been revealed that concerned documents were drawn up under orders from former Defense Minister Han Min-koo. The investigation has yet to determine whether the DSC was preparing for the possibility of martial law being declared or planning a coup, as claimed by some in the ruling bloc.

As the investigation expands, investigators raided the home of retired Army Gen. Jang Jun-kyu on Friday, and questioned former DSC commander Army Lt. Gen. Lee Suk-koo on Sunday.

Jang served as the Army chief of staff from September 2015 to August 2017. The DSC documents regarding a martial law situation give the Army chief of staff command of the units involved in enforcing martial law.

According to investigators, the raid was conducted to determine Jang’s involvement in the developments. Along with Jang’s home, the investigators also searched the residences of Han and former DSC chief Cho Hyun-chun on the same day.

The presidential office, meanwhile, is looking into alleged irregularities in the process of the Defense Ministry reporting related issue to Cheong Wa Dae.

It has been alleged the current defense minister was aware of the martial law documents for some time before informing the presidential office.

Song has also been accused by a DSC colonel of stating that the military reviewing plans for enforcing order in times of unrest is within the boundaries of law during a session of the parliamentary defense committee. Song denied the allegations, accusing Col. Min Byeong-sam of being untruthful.